The cooling effect of the Chunlan window-type air conditioner has decreased. Maintenance process MT.
**Decreased Cooling Performance of Chunlan Window Air Conditioner**
**Fault Phenomenon:** A Chunlan window air conditioner that has been used for several years is experiencing a decline in cooling performance and does not shut off automatically. After prolonged operation, ice formation is observed on the evaporator. Upon checking, it is found that the airflow from the outlet has decreased.
**Analysis and Maintenance:** The low temperature of the evaporator indicates that the refrigeration system is functioning properly overall. Based on the reduced airflow, the fault is preliminarily judged to be in the air circulation section. First, the panel filter was inspected, with no dust or other debris found. The exterior casing was then disassembled for further inspection: the start capacitor of the fan was intact, and the fan was operating normally; the air duct also showed no abnormalities.
Upon closer observation, it was discovered that a metal mesh screen was attached to the air intake behind the evaporator. The mesh holes of this metal screen had been completely blocked by rust, causing poor air circulation and resulting in the decline of the air conditioner's cooling performance. During the refrigeration process, condensation water formed on the surface of the evaporator causes rusting and blockage of the metal mesh near the evaporator, which prevents air from passing through smoothly and affects the cooling effect.
During repairs, the rust was thoroughly removed using a copper wire brush. Considering that the air conditioner's panel already has a filter, having this additional metal mesh screen is unnecessary. Therefore, it was decided to remove it to eliminate potential future issues (alternatively, the metal mesh screen could be replaced with a plastic one to prevent rust blockage from affecting the cooling performance again).
**Source of Article:** http://blog.tianya.cn/blogger/blog_main.asp?BlogID=3480078
